1. Field of the Invention
This invention is found in a method and apparatus for treating wounds of a person, in particular, for treating wounds located on extremities or highly contoured, non-planar surfaces of the person.
2. Description of Related Art
In order to prevent or limit infection and shorten the healing process, wounds are commonly covered with sterile bandages. The bandages include gauze that may be held in place over a wound with adhesive tape or other binding means. As noted in a prior, commonly assigned patent, U.S. Pat. No. 5,817,145, gauze bandages have several limitations. First, the gauze bandages do not filly isolate the wound from the surrounding environment and the gauze may adhere to the wound, lengthening the healing process. In addition, the bandages do not thermally regulate the wound environment.
In order to overcome these limitations and others of the prior art, U.S. Pat. No. 5,817,145 teaches a wound treatment device that treats a wound without contacting it. The device includes at least three elements: a wound attachment portion, a standoff portion, and a transition portion. This patent is incorporated by reference for its teachings of such a wound treatment device. The wound attachment portion forms a first plane that is received on the person""s skin and includes an adhesive portion for adhering to the person""s skin about a wound. The standoff portion defines a second plane above the wound and includes an opening between the first and second planes. The transition portion covers the opening at the second plane, thereby forming a wound treatment volume, connects the attachment portion to the standoff portion and enables the attachment portion to move in conjunction with movement of a person. As described in the ""145 patent, each portion is flexible to accommodate movement. While the described wound treatment device is suitable for treating wounds on non-planar surfaces of the person, e.g., the extremities of the person, there may be some highly contoured body portions where its effectiveness might be compromised. Thus, the need exists for a wound treatment apparatus and method for treating wounds located on highly contoured, non-planar surfaces of a person.
This invention is practiced both as a modular wound treatment apparatus and as a method for treating wounds with such an apparatus. The apparatus is modular in that it comprises separate component parts that may be assembled more or less completely for use. The component parts are a standoff and a strip or sheet of flexible material. At least one surface of the sheet of material has an adhesive material or structure that permits the sheet of material to be attached to the skin, if not also to the standoff. The method includes placing the standoff about or near a wound. The standoff defines or forms a space sufficient to accommodate the wound. Preferably the standoff is flexible, which enables it to conform to the surface area peripheral to the wound (xe2x80x9cthe periwoundxe2x80x9d). The method also includes attaching the sheet of material over the standoff, with the adhesive material or structure facing the standoff and skin. The standoff elevates the sheet of material over the wound, forming a treatment volume between itself, the sheet of material and the wound. By this method, the standoff and sheet of material are assembled to form a bandage that provides a sealed environment over the wound. Advantageously, the bandage, when assembled, is entirely or largely out of contact with the wound. This modular bandage and this method of treating a wound are particularly useful when the surface of the person about the wound is non-planar and highly contoured, e.g. when the dermal surface about the wound is located on an extremity of the person. While this description generally references the treatment of a person, it should be understood that the devices described herein may be used in the treatment of animals as well.
The standoff may be formed from an absorbent material, such as foam, in order to support autolytic debridement of a wound. This process is explained in detail in U.S. patent application Ser. No. 09/056,121, filed Apr. 6, 1998, which is commonly assigned with this application, and which is incorporated herein by reference.
In shape and structure, the standoff may be embodied as a single piece of flexible material having a plurality of removable sections. One or more of the sections may be removed in order to provide an opening in the standoff having a shape and area sufficient to surround a wound. In another embodiment, the standoff may include one or more elements placed about or near the wound. In all cases, the role of the standoff is to elevate the sheet of material above and out of contact with the wound.
The sheet of material includes a sheet of flexible material that may have a moisture vapor transmission rate (MVTR). In addition, the sheet of material includes adhesive for attachment onto the surface of the person over the standoff.
Finally, the modular bandage may also include a heater on or in the sheet of material, over the standoff. In this case, the heater is used to regulate the thermal conditions of the wound environment in the treatment volume formed by the standoff and sheet of material. Regulation of the thermal conditions of the treatment volume may, among other objectives, include therapies that target normothermic conditions. Normothermia for the human body can be defined as temperatures in the range of 36xc2x0 C.-38xc2x0 C.